Is Fanāʾ the Erasure of the Servant or the Manifestation of the Lord?

The continued existence of beings is the manifestation of the Creator’s will that they endure; their passing away is the manifestation of His will that they perish.
Both endurance and perishing are signs of the Exalted Lord’s will, like confirmation and erasure.
In either state—whether endurance or perishing—the glory, perfection, and will of God are manifested in their fullness.
Neither endurance, nor perishing, nor anything else can stand in the way of the manifestation of God’s will!

يس : 82 إِنَّما أَمْرُهُ إِذا أَرادَ شَيْئاً أَنْ يَقُولَ لَهُ كُنْ فَيَكُونُ
His command is such that whenever He wills something, He only says to it, “Be!” and it comes into being at once.

هود : 107 خالِدينَ فيها ما دامَتِ السَّماواتُ وَ الْأَرْضُ إِلاَّ ما شاءَ رَبُّكَ إِنَّ رَبَّكَ فَعَّالٌ لِما يُريدُ
They will abide there for as long as the heavens and the earth endure, unless your Lord wills otherwise. Your Lord does whatever He wills!

الرعد : 39 يَمْحُوا اللَّهُ ما يَشاءُ وَ يُثْبِتُ وَ عِنْدَهُ أُمُّ الْكِتابِ
God effaces whatever He wills and confirms whatever He wills; and with Him is the Mother of the Book.